Claude Gordon, Tongue Level Exercises for Trumpet (Carl Fischer, 1981), 21.
Things to remember when you practice
1. 5 times 10 breathing exercise before you begin
2. Each exercise tongued then slurred
3. BIG BREATH – CHEST UP – SHOULDERS BACK (NOT UP)
4. WATCH THE TONGUE
This exercise is part of a customized 5 part lesson plan. My teacher, Bruce Haag is a certified Claude Gordon instructor, and the practice routines he assigns serve to set goals for progress and to help the student understand exactly what is causing the progress.